PWX-30114: Handling error in store_kv (#143)

When a lock reaches tryDuration, it returns and error
    that the key already exists. It was not being returned.

Signed-off-by: Naveen Revanna <nrevanna@purestorage.com>

Author: nrevanna

store/store_kv.go

@@ -90,6 +90,9 @@ func (kv *kvStore) getFullLockPath(key string) string {
 func (kv *kvStore) LockWithKey(owner, key string) (*Lock, error) {
 	fullPath := kv.getFullLockPath(key)
 	kvPair, err := kv.lockWithKeyHelper(owner, fullPath)
+	if err != nil {
+		return nil, err
+	}
 	kvPair.lockedWithKey = true
 	return kvPair, err
 }